save project

diy1.py

@@ -3,11 +3,14 @@
 每次移动都增加画笔移动的长度，并旋转91°，重复执行300次，查看效果
 """
 import turtle
-
+screen=turtle.Screen()
+screen.bgcolor("black")
+sb=["red","green","cyan","violet"]
 pen = turtle.Pen()
 # 请创造师在下面接着创作
 distance=1
 for i in range(300):
+    pen.pencolor(sb[i%4])
     pen.forward(distance)
     distance+=1
     pen.right(91)